Production of esters of phosphoric acid and thionophosphoric acid



PRODUCTION OF. ESTERS F PHOSPHORIC ACID THIONOBHOSPHORIC ACID Harald Schroeder and Heinz Polilemann, Ludwigshafen (Rhine), Herbert Stummeyer, Mannheim-and Heinrich Adolphi, Limburgerhof, Pfalz, Germany, assignors to Badische Aniiin- & soda -Fabrik Aktiengesellschaft, Ludwigshafeh. (Rhine), Germany No; Drawing. Application September 24, 195% SerialNo. 685,810

Claims priority, appli cation.Germany-September 28, 1.95.6 C ims 9-46 This invention relates to aprocess for the production I of alkylphosphoric acid or alkylthionophosphoric acid esters by the reaction of dialkylphosphoric or dialkylthionophosphoric acid halides with hydroxyor dihydroxysuecinic acids or their half esters.

It is already known that neutral esters of orthophosphoric acid or thionophosphoric acid are obtained by allowing compounds containing hydroxy groups, as for example alcohols or phenols, to act on phosphorus oxyhalides, monochlorides or dichlorides of alkoxyphosphoric acid; or on the corresponding thionophosphorus comq n c mpoundsot hi k nd. ar a mi y been p par in large numb rs nd exhibit ins ct ng a or rodenticidal activity. of varying strength.

Wehavenow fqundthata new class ot'alkylphosphoric a d r; t ion p csp ric. acid esters are obtaiuedby rea n a d al phcsph c. a h l e. of t e g ne formula 'mo Hal 7 V (r) in which R and R represent alkyl radicals with l to 4 carbon atoms and X an oxygen or a sulfur atom and Hal a halogen atom with hydroxysuccinic acids or their half esters of the general formula HO-CH-CQOR;

Ra-C 11-0 0 0H in which R represents a hydrogen atom, a hydroxyl group, whichmay if desired also be etherified or esterified, or a halogen atom and- R a hydrogen atom or an alkyl group, R representsin particular an alkoxy radical. with up to six carbon atoms, for example a methoxy, ethoxy, propoxy or butoxy radical or a carboxy-alkyl radical with 2 to 6 carbon atoms, especially an acetylor propionyl radical.

lf R represents a hydroxyl group, either one or both of the hydroxyl groups of the dihydroxysuccinic acid orits half ester may react depending on the ratio of the initial amounts, i.e. when using an excess of the succinic acid component only one hydroxy group is esterified, and inv the converse case both hydroxyl' groups are esterified. In addition, however, one, or both carboxylic groups of the hydroxysuccinic acids or their half esters or also one or both carboxylic groups of the dihydroxysuccinic acid may be reacted with dialkylphosphoric-acid or dialkylthionophosphoric acid halides. In this case a corresponding excess of dialkylphosphon'c or -th ionophosphoxic acid halide is used for the reaction. R represents especially an alkyl group with 1 to 6 carbon atoms, for example a methyl, ethyl or propyl group. In this reaction substances of the following formula are obtained Bron-00B In this formulaX is. a. radical of, dialkylthionopho sphorie acid with the formula wherein R is an alkyl group with l to 4 carbon atoms, A-is a radical selected from the group consisting of hydroxyl, CR and X; B is a radical selected from the group consisting of, hydroxyl, CR and X; D is a radical selected from the group consisting of hydroxyl, OCOR 0R X and halogen, and A and B may not simultaneously be 0R Suitable hydroxysuccinieacidsor hydroxysuccinic acid half esters. according to the described formula are for example. alpha hydroxysuccinic acid, alpha-hydroxysuccinic acid. monomethyl ester, alpha-hydroxysuccinic acid monoethylester, alpha.beta-dihydroxysuccinic acid, alpha.- beta-dihydroxysu'ccinic acid monomethyl ester, alphahydroxy-beta-chlorsuccinic acid and alpha-hydroxy-beta-.

methoxysuccinieacid and their half esters.

Suitable halides, of Qo-diallcylphosphoric or -thionophosphoric acids for the reaction are for example dim ethyl j diethyl dipropyh' or dibutyl-phosphoric or -thionophosphoric acid chloride, bromide or iodide.

' In the reaction of'one hydroxy group it is suitable to react the said initial materials with each other in equivalent amounts. If it isdesiredxhowever to react two or more. hydroxyl groupswith dialkyl-phosphoric or -thionophosphoric. acid, halides, these must be used in at least a double or triple. excess.

The reaction is suitably carried out in the presence of a solventfas for example a hydrocarbon, such as petroleum ether, cyclohexane, benzene or toluene, or a ample-between, 15 and,120 C., preferably between 30 and 80 C. The hydrogen halide formed is advanta- The halogen, is especially bromine or chlorine. Y

. by weight.

geously bound by the addition ofiagents which bind hydrogen halide, as for example tertiary amines, such as triethylamine or pyridine, or by alkali carbonates or alkali bicarbonates. The liquid base can;wholly or partly replace the solvent otherwise necessary.

The substances accessible for the first time according to this invention are generally characterized by a good insecticidal action with low toxicity.

In particular, the substances are useful for combatting Diptera, i.e. Musca domestica, Stomoxys calcitrans (imago. and larvae), Pegomya, hyosciami; Aphiodoidea i.e. Mycus persicae, Ifya lopthems a'rlmdinis and Tetranychidae.

It is surprising that in the reaction of substances which still contain. free carboxyl groups with dialkylphosphoric or -thionophosphoric acidhalides there should be obtained insecticideswhich are superior to the corresponding compounds originating from hydroxysuccinic, acid dialkyl estersbyamultiple in, their activity.

' "Thefollowijng examples will. further illustrate this invention but the invention is not limited to these examples. The parts specified in the examples are parts Exgmgle 1,;

1340 parts; of alpha-hydroxysuccinic, acid are dis solved in a mixture of 1650 parts of pyridine and 2000 parts of benzene. 1880 parts of 0.0-diethylthionophos- V phoric acid chloride, are slowly allowed to flow into this Patented May 17, 1960 solution and the temperature is kept at 20 to 25' C. Then the product is stirred for 5 hours at 50 C., 1500 parts of benzene are added when it is cold, washed with water, dried and the solvent distilled off under reduced pressure. There are obtained as a residue 1243 parts of 0.0-diethyl-O-(.alphabeta-dicarboxylethyl)- thionophosphate as a yellow-brown non-distillable oil. This is 43.5% of the theoretical yield. The product has the structural formula canto s Example 2 134 parts of malic acid are suspended in 1000 parts of benzene and stirred with 650 parts of pyridine with good stirring. Then 376 parts of diethylthionophosphoric acid chloride are dripped into the mixture, it is stirred for 5 hours at 45 to 50 C., 300 parts of water are added and the mixture made slightly acid with dilute hydrochloric acid. It is shaken several times with water, dried and the benzene layer dried and the solvent then evaporated under reduced pressure. There are obtained as a residue 330 parts of the new compound with the formula C I-1 8 15 as a brownish non-distillable oil. The yield is 76% of the'theoretical yield.

Example 3 13.4 parts of malic acid are dissolved in' 100 parts of benzene with the aid of 70 parts of pyridine. Then while stirring well, 56.4 parts of diethylthionophosphoric acid chloride are allowed to flow in and the whole stirred for another 5 to 6 hours at 50 C. It is allowed to cool, 100 parts of benzene are added and 30 parts of water, the whole is made slightly acid with dilute hydrochloric acid and then shaken up with water. The benzene solution is'dried, the benzene distilled off under reduced pressure and 41 parts of the new compound having the formula C H O S P are obtained as a brownish non-distillable oil with very good insecticidal properties. The yield is 69.5% of the theoretical yield. The reaction product has the formula Example 4 y 134 parts of malic acid are dissolved in 600 parts of methylenechloride and 330 parts of dry pyridine with good stirring. Then 481 parts of 0.0-dimethylthionophosphoric acid chloride are dripped under good stirring into the mixture. The mixture is stirred for five hours at a temperature from 50,to 55 C. After cooling to 1 room temperature 100 parts of water are added, organic layer is separated and stirred two times with 100 parts of water, dried and the solvent distilled off under reduced pressure. There are obtained as a residue 360 parts of a yellow non-distillable oil of the formula:

' 01130 S s 0cm.

P-o-cr-:t-c'oo-i onto ocn" CH -COO-P H 7 Example 5 37.5 parts of alpha.beta-dihydroxysuccinic acid are stirred with 150 parts of chloroform and 40 parts of pyridine. To this mixture are dripped under good stirring 47 parts of O.Q-diethylthionophosphoric acid chlo; ride at room temperature. hours at 50 C. After cooling the mixture is worked up as described above. 30 parts of a compound with good insecticidal action are obtained as a yellow oil.

Example 6 Example 7 168 parts of alpha-hydroxy-beta-chloro succinic acid are suspended in 650 parts methylene chloride. Then 564 parts of 0.0-diethylthionophosphoric acid chloride are dripped into the mixture under good stirring.

The mixture is stirred 4 hours at to C. and cooled to room'temperature. 100 parts of water are added and then the organic layer is separated and ester are dissolved in 330 parts of pyridine.

stirred two times with water. After separation of pyridine and pyridinehydrochloride the organic layer is worked up as described above.

420 parts of a compound of the formula CaHgO s 8 00m.

i 0cH0o0-i sHsO 00113; are obtained as a yellow non-distillable oil.

Example 8 162 parts of alpha-hydroxy succinic acid monoethyl 376 parts of 0.0-diethylthionophosphoric acid chloride are dripped into the solution which is stirred 5 hours at 40 to 50 C., cooled and worked up as described above.

295 parts of a compound of the formula are obtained as a yellow oil. We claim:

' 1. A process for the production of alkylphosphoric acid esters which comprises reacting a dialkylthionophosphoric acid halide of the general formula in which R; and R represent alkyl radicals with 1 to 4 The mixture is stirred 5'.

carbon atoms, and Hal a halogen atom with a compound of the general formula in which R is a radical selected from the group consisting of hydrogen, bromine, chlorine, a hydroxyl and R is a radical selected from the group consisting of hydrogen and lower alkyl at a temperature from about to about 120 C.

2. A process as claimed in claim 1 wherein the reaction is carried out in the presence of a tertiary amine capable of binding hydrogen halide.-

3. A process as claimed in claim 2 wherein pyridine is used as the agent for binding hydrogen halide.

4. A compound of the general formula wherein X is a radical of dialkylthionophosphoric acid with the formula wherein R is a alkyl group with 1 to 4 carbon atoms; A is a radical selected from the group consisting of hydroxyl, OR, and X; B is a radical selected from the group consisting of hydroxyl, CR and X; D is a radical selected from the group consisting of hydroxyl, X, ch1o rine and bromine, and wherein A and B may not simultaneously be 0R 5. A compound of the formula 6 6. A compound of the formula 0,2150 5 s i o-cH-o0o-i mmo 00:15.

0 Cam 7. A compound of the formula 1 -o0Hc00--i OaHaO OgmO References Cited in the file of this patent UNITED STATES PATENTS 2,578,652 \Cassaday Dec. 18, 1951 2,625,536 Kirby Jan. 13, 1953 2,645,657 Rudel et a1. July 14, 1953 2,713,018 Johnson July 12, 1955 2,788,359 Grundmann et a1 Apr. 9, 1957 FOREIGN PATENTS 1,006,854 Germany ...J Apr. 25, 1957 1,011,416 Germany July 4, 1957 

1. A PROCESS FOR THE PRODUCTION OF ALKYPHOSPHORIC ACID ESTERS WHICH COMPRISES REACTING A DIALKYLTHIONOPHOSPHORIC ACID HALIDE OF THE GENERAL FORMULA
 4. A COMPOUND OF THE GENERAL FORMULA 